The agreement, consistently supported by the Green Party but vehemently opposed by National, creates non-legally binding conditions for countries to "enable all migrants to enrich our societies through their human, economic and social capacities," according to the UN.

The announcement came after Mr Peters took legal advice confirming New Zealand's sovereignty would not be compromised by adopting the agreement.

"The Government would not support the UN compact if it compromised New Zealand's sovereignty or could in any way take precedence over our immigration or domestic laws. But the compact does not do that," said Mr Peters.

Despite the legal advice from Crown Law, Mr Peter's decision has been heavily criticised by some online concerned about the Compact's effect on New Zealand's migration settings.

That criticism has extended to the New Zealand Red Cross, which on Wednesday tweeted support for the Compact after Mr Peters announced his decision.

"This is great news. The Global Compact for Migration is a rare opportunity to develop a new approach to migration that is more effective and human, protects dignity, and saves lives," the tweet said.

In response, some users tweeted that they would no longer donate to the charity, which helps with everything from refugee programmes to Meals on Wheels, to aiding in the aftermath of natural disasters.

"No more donations from me, this is the last straw," said one user, while another noted: "We are substantial donors to you. It's a family tradition. It ended as of today".

"I shall never donate to the Red Cross again. I won't frequent your stores and I'll impress on all my friends and family to do likewise," said one tweet.

New Zealand Red Cross's general manager for migration, Rachel O'Connor, told Newshub that the charity was "surprised but not concerned by the negative reaction".

"It is only a small number of people, and we know Kiwis on the whole care about ensuring all people who are migrating have access to humanitarian assistance, protection, health care and basic services."

One of the principles the Red Cross says it stands for is "neutrality" - a point one Twitter user noted in response to the charity's support.

"In order to continue to enjoy the confidence of all, the Movement may not take sides in hostilities or engage at any time in controversies of a political, racial, religious or ideological nature," the charity's website states.

But Ms O'Connor said the Red Cross is "in the business of saving lives and alleviating suffering, both here in Aotearoa and overseas".

"That is why we support this compact - if the actions in it are implemented, we believe it has the potential to save lives."

Criticism towards the Compact has been generally related to the belief that it would overrule national sovereignty - something the National Party has been concerned about as well.

"While not binding, the Compact could restrict the ability of future governments to set immigration and foreign policy, and to decide on which migrants are welcome and which aren't," said leader Simon Bridges earlier this month.

But Mr Peters said the legal advice has debunked falsehoods and misguided perceptions about the Compact.

New Zealand First's Facebook account has also been inundated with comments stating the party would be hurt at the next election as a result of the decision.

"I voted for you, I encouraged my family & friends to as well, because I thought you were the best option, but you did the opposite of what your constituents wanted, you betrayed your own people Winston, your own voters, not cool," said one user.

While emphasising the need for international cooperation, the Compact explicitly recognises the sovereignty of individual nations.

"It fosters international cooperation among all relevant actions on migration, acknowledging that no State can address migration alone, and upholds the sovereignty of States and their obligations under international law," the Compact states.